1. Field of the Invention
The disclosure contained in this document relates to a retractable step or ramp that is automatically or manually extensible from the floor of a railcar or other means of transportation for the boarding and exit of passengers, and particularly to a retractable step portion or ramp portion that is selectively extensible outwardly from either side of the railcar or other vehicle to enable boarding and exit of passengers through either door on opposed sides of the railcar or other vehicle.
2. Description of Related Art
There is a need for ambulatory people and those unable to climb up steps to be able to gain access to public transportation systems for employment, education, recreation and other purposes. Commuter rail systems, in particular, have difficulty providing suitable access to all passengers, including the elderly and passengers with mobility limitations due to variable horizontal and vertical gaps between the railcars and passenger boarding platforms. There are several reasons for the variability in horizontal and vertical gap. Many commuter rail systems share rail platforms with freight trains, and freight car bodies are generally wider than the bodies of passenger railcars, resulting in a horizontal gap between passenger railcars and high-level platforms. Also, many train stations are built along a curved track, which causes variation in a horizontal gap between the platform and railcar. Often, commuter railcars are equipped with a pneumatic leveling system causing railcar floor heights to fluctuate relative to the height of the rail platform. Finally, when track maintenance crews reset the tracks, the tracks are lifted up and a new track bed is laid down. Then the tracks are lowered on top of a higher bed thereby raising the railcar floor to ground level and causing a larger vertical gap. A study of current commuter rail systems that share tracks with freight trains and access only high-level platforms, indicated that the horizontal gap can be up to about 11 inches and the vertical gap about 6 inches. In order to bridge gaps of these dimensions, certain requirements must be met, for example, as promulgated by various governmental agencies.
In the United States, regulations have been established under the Americans with Disabilities Act (ADA) that set forth the requirements for bridging the gap between transit vehicles and platforms in various transportation facilities. The Code of Federal Regulations at 37 CFR part 1192 provides that ramps can have a slope of 1 inch in height over a length of 10 inches when bridging a maximum rise of 6 inches, a slope of between 1 inch in height to 8 inches in length, and 1 inch in height to 10 inches in length is permitted for a maximum rise of 3 inches. The ramp must also have a clear width at the surface of 30 inches and each side of the ramp must have a barrier at least 2 inches high to prevent mobility aid wheels from slipping off the side of the ramp.
In the United Kingdom, the Strategic Rail Authority published a Code of Practice in March 2005 concerning “Train and Station Services for Disabled Passengers”. The Code sets forth various requirements for powered or manually operated ramps and powered lifts, including that the operator of the vehicle shall provide assistance to a disabled person in a wheelchair unless the gradient of the ramp above the horizontal plane is 8% or less. The Code also requires that a protective rim be provided along each side of the ramp at least 2″ higher than the surface of the ramp.
These stipulations represent only a portion of the various regulations currently in force in the United States and United Kingdom. Presently, available step or ramp devices are solely used for wheelchair access or are not capable of automatically or manually bridging varying horizontal and vertical gaps of the magnitude found in current commuter rail systems (including those that share tracks with freight trains) and complying with the requirements of government regulations for bridging such gaps.
Manual “bridge plates” have been used for high floor-level commuter rail systems that access high-level platforms. Typically the bridge plate is a fixed device that is manually placed across a gap. Most such devices are about 29 inches wide and about 32 inches long, which means that to meet governmental requirements for ramp angles, the bridge plate cannot be used for vertical gaps that are higher than 4 inches. Using a bridge plate on a gap that is 6 inches high can be difficult and risky for people who independently drive their wheelchair onto a railcar. Also, using a manual bridge plate is time consuming and increases the potential for rail delays. Current systems require assistance to use them. Automatic wheelchair lift-type mechanisms have also been used but are complex and take up valuable railcar boarding space.
Various ramp-type systems have been disclosed in patents. U.S. Pat. No. 5,636,399 to Tremblay et al., discloses a wheelchair ramp assembly which includes a platform that is stored under or on a bus or other vehicle floor. U.S. Pat. No. 6,484,344 to Cooper, discloses a retractable access ramp which has a housing that may be coupled to steps such that a top wall of the housing is flush with a top surface of the steps. However, each of these ramp systems suffers from various deficiencies.
For instance, none of the prior art systems provides for a ramp system that can be positioned on the floor of a railcar and has a low-profile to avoid interference with passenger traffic entering and exiting the railcar. Additionally, it is important for the ramp system to be easily retrofitted into existing railcars so that these railcars can simply and inexpensively made to comply with ADA requirements.
Accordingly, a need exists for a ramp assembly that is capable of bridging varying vertical gaps of up to 6 inches or more and varying horizontal gaps of up to 12 inches or more and provides access to either of the doors on opposite sides of a railcar or other vehicle. A further need exists for a ramp that has a low-profile and can be easily retrofitted into an existing railcar.